Chicago is an American
rock band formed in 1967 in
Chicago, Illinois. The self-described "rock and roll band with horns" began as a politically charged, sometimes experimental, rock band and later moved to a predominantly softer sound, generating several hit ballads. The group had a steady stream of hits throughout the 1970s and 1980s. Second only to
The Beach Boys in
Billboard singles and albums chart success among American bands, Chicago is one of the longest-running and most successful rock groups, and one of the
world's best-selling groups of all time, having sold more than 100 million records.